opal/opal — pull request #479 by elia (2014-01-09 10:09:25+00:00)
Title: Error parsing color gem

```ruby
# An RGB colour object.
class Color::RGB
# The format of a DeviceRGB colour for PDF. In color-tools 2.0 this will
# be removed from this package and added back as a modification by the
# PDF::Writer package.
PDF_FORMAT_STR = "%.3f %.3f %.3f %s"

class << self
# Creates an RGB colour object from percentages 0..100.
#
# Color::RGB.from_percentage(10, 20 30)
def from_percentage(r = 0, g = 0, b = 0)
from_fraction(r / 100.0, g / 100.0, b / 100.0)
end

# Creates an RGB colour object from fractional values 0..1.
#
# Color::RGB.from_fraction(.3, .2, .1)
def from_fraction(r = 0.0, g = 0.0, b = 0.0)
colour = Color::RGB.new
colour.r = r
colour.g = g
colour.b = b
colour
end

# Creates an RGB colour object from an HTML colour descriptor (e.g.,
# "fed" or "#cabbed;".
#
# Color::RGB.from_html("fed")
# Color::RGB.from_html("#fed")
# Color::RGB.from_html("#cabbed")
# Color::RGB.from_html("cabbed")
def from_html(html_colour)
html_colour = html_colour.gsub(%r{[#;]}, '')
case html_colour.size
when 3
colours = html_colour.scan(%r{[0-9A-Fa-f]}).map { |el| (el * 2).to_i(16) }
when 6
colours = html_colour.scan(%r<[0-9A-Fa-f]{2}>).map { |el| el.to_i(16) }
else
raise ArgumentError
end

Color::RGB.new(*colours)
end
end

# Compares the other colour to this one. The other colour will be
# converted to RGB before comparison, so the comparison between a RGB
# colour and a non-RGB colour will be approximate and based on the other
# colour's default #to_rgb conversion. If there is no #to_rgb conversion,
# this will raise an exception. This will report that two RGB colours are
# equivalent if all component values are within COLOR_TOLERANCE of each
# other.
def ==(other)
other = other.to_rgb
other.kind_of?(Color::RGB) and
((@r - other.r).abs <= Color::COLOR_TOLERANCE) and
((@g - other.g).abs <= Color::COLOR_TOLERANCE) and
((@b - other.b).abs <= Color::COLOR_TOLERANCE)
end

# Creates an RGB colour object from the standard range 0..255.
#
# Color::RGB.new(32, 64, 128)
# Color::RGB.new(0x20, 0x40, 0x80)
def initialize(r = 0, g = 0, b = 0)
@r = r / 255.0
@g = g / 255.0
@b = b / 255.0
end

# Present the colour as a DeviceRGB fill colour string for PDF. This will
# be removed from the default package in color-tools 2.0.
def pdf_fill
PDF_FORMAT_STR % [ @r, @g, @b, "rg" ]
end

# Present the colour as a DeviceRGB stroke colour string for PDF. This
# will be removed from the default package in color-tools 2.0.
def pdf_stroke
PDF_FORMAT_STR % [ @r, @g, @b, "RG" ]
end

# Present the colour as an HTML/CSS colour string.
def html
r = (@r * 255).round
r = 255 if r > 255

g = (@g * 255).round
g = 255 if g > 255

b = (@b * 255).round
b = 255 if b > 255

"#%02x%02x%02x" % [ r, g, b ]
end

# Present the colour as an RGB HTML/CSS colour string (e.g., "rgb(0%, 50%,
# 100%)"). Note that this will perform a #to_rgb operation using the
# default conversion formula.
def css_rgb
"rgb(%3.2f%%, %3.2f%%, %3.2f%%)" % [ red_p, green_p, blue_p ]
end

# Present the colour as an RGBA (with alpha) HTML/CSS colour string (e.g.,
# "rgb(0%, 50%, 100%, 1)"). Note that this will perform a #to_rgb
# operation using the default conversion formula.
def css_rgba
"rgba(%3.2f%%, %3.2f%%, %3.2f%%, %3.2f)" % [ red_p, green_p, blue_p, 1 ]
end

# Present the colour as an HSL HTML/CSS colour string (e.g., "hsl(180,
# 25%, 35%)"). Note that this will perform a #to_hsl operation using the
# default conversion formula.
def css_hsl
to_hsl.css_hsl
end

# Present the colour as an HSLA (with alpha) HTML/CSS colour string (e.g.,
# "hsla(180, 25%, 35%, 1)"). Note that this will perform a #to_hsl
# operation using the default conversion formula.
def css_hsla
to_hsl.css_hsla
end

# Converts the RGB colour to CMYK. Most colour experts strongly suggest
# that this is not a good idea (some even suggesting that it's a very bad
# idea). CMYK represents additive percentages of inks on white paper,
# whereas RGB represents mixed colour intensities on a black screen.
#
# However, the colour conversion can be done. The basic method is
# multi-step:
#
# 1. Convert the R, G, and B components to C, M, and Y components.
# c = 1.0 - r
# m = 1.0 - g
# y = 1.0 - b
# 2. Compute the minimum amount of black (K) required to smooth the colour
# in inks.
# k = min(c, m, y)
# 3. Perform undercolour removal on the C, M, and Y components of the
# colours because less of each colour is needed for each bit of black.
# Also, regenerate the black (K) based on the undercolour removal so
# that the colour is more accurately represented in ink.
# c = min(1.0, max(0.0, c - UCR(k)))
# m = min(1.0, max(0.0, m - UCR(k)))
# y = min(1.0, max(0.0, y - UCR(k)))
# k = min(1.0, max(0.0, BG(k)))
#
# The undercolour removal function and the black generation functions
# return a value based on the brightness of the RGB colour.
def to_cmyk
c = 1.0 - @r.to_f
m = 1.0 - @g.to_f
y = 1.0 - @b.to_f

k = [c, m, y].min
k = k - (k * brightness)

c = [1.0, [0.0, c - k].max].min
m = [1.0, [0.0, m - k].max].min
y = [1.0, [0.0, y - k].max].min
k = [1.0, [0.0, k].max].min

Color::CMYK.from_fraction(c, m, y, k)
end

def to_rgb(ignored = nil)
self
end

# Returns the YIQ (NTSC) colour encoding of the RGB value.
def to_yiq
y = (@r * 0.299) + (@g * 0.587) + (@b * 0.114)
i = (@r * 0.596) + (@g * -0.275) + (@b * -0.321)
q = (@r * 0.212) + (@g * -0.523) + (@b * 0.311)
Color::YIQ.from_fraction(y, i, q)
end

# Returns the HSL colour encoding of the RGB value. The conversions here
# are based on forumlas from http://www.easyrgb.com/math.php and
# elsewhere.
def to_hsl
min = [ @r, @g, @b ].min
max = [ @r, @g, @b ].max
delta = (max - min).to_f

lum = (max + min) / 2.0

if Color.near_zero?(delta) # close to 0.0, so it's a grey
hue = 0
sat = 0
else
if Color.near_zero_or_less?(lum - 0.5)
sat = delta / (max + min).to_f
else
sat = delta / (2 - max - min).to_f
end

# This is based on the conversion algorithm from
# http://en.wikipedia.org/wiki/HSV_color_space#Conversion_from_RGB_to_HSL_or_HSV
# Contributed by Adam Johnson
sixth = 1 / 6.0
if @r == max # Color.near_zero_or_less?(@r - max)
hue = (sixth * ((@g - @b) / delta))
hue += 1.0 if @g < @b
elsif @g == max # Color.near_zero_or_less(@g - max)
hue = (sixth * ((@b - @r) / delta)) + (1.0 / 3.0)
elsif @b == max # Color.near_zero_or_less?(@b - max)
hue = (sixth * ((@r - @g) / delta)) + (2.0 / 3.0)
end

hue += 1 if hue < 0
hue -= 1 if hue > 1
end
Color::HSL.from_fraction(hue, sat, lum)
end

# Mix the RGB hue with White so that the RGB hue is the specified
# percentage of the resulting colour. Strictly speaking, this isn't a
# darken_by operation.
def lighten_by(percent)
mix_with(White, percent)
end

# Mix the RGB hue with Black so that the RGB hue is the specified
# percentage of the resulting colour. Strictly speaking, this isn't a
# darken_by operation.
def darken_by(percent)
mix_with(Black, percent)
end

# Mix the mask colour (which must be an RGB object) with the current
# colour at the stated opacity percentage (0..100).
def mix_with(mask, opacity)
opacity /= 100.0
rgb = self.dup

rgb.r = (@r * opacity) + (mask.r * (1 - opacity))
rgb.g = (@g * opacity) + (mask.g * (1 - opacity))
rgb.b = (@b * opacity) + (mask.b * (1 - opacity))

rgb
end

# Returns the brightness value for a colour, a number between 0..1. Based
# on the Y value of YIQ encoding, representing luminosity, or perceived
# brightness.
#
# This may be modified in a future version of color-tools to use the
# luminosity value of HSL.
def brightness
to_yiq.y
end
# Convert to grayscale.
def to_grayscale
Color::GrayScale.from_fraction(to_hsl.l)
end
alias to_greyscale to_grayscale

# Returns a new colour with the brightness adjusted by the specified
# percentage. Negative percentages will darken the colour; positive
# percentages will brighten the colour.
#
# Color::RGB::DarkBlue.adjust_brightness(10)
# Color::RGB::DarkBlue.adjust_brightness(-10)
def adjust_brightness(percent)
percent /= 100.0
percent += 1.0
percent = [ percent, 2.0 ].min
percent = [ 0.0, percent ].max

hsl = to_hsl
hsl.l *= percent
hsl.to_rgb
end

# Returns a new colour with the saturation adjusted by the specified
# percentage. Negative percentages will reduce the saturation; positive
# percentages will increase the saturation.
#
# Color::RGB::DarkBlue.adjust_saturation(10)
# Color::RGB::DarkBlue.adjust_saturation(-10)
def adjust_saturation(percent)
percent /= 100.0
percent += 1.0
percent = [ percent, 2.0 ].min
percent = [ 0.0, percent ].max

hsl = to_hsl
hsl.s *= percent
hsl.to_rgb
end

# Returns a new colour with the hue adjusted by the specified percentage.
# Negative percentages will reduce the hue; positive percentages will
# increase the hue.
#
# Color::RGB::DarkBlue.adjust_hue(10)
# Color::RGB::DarkBlue.adjust_hue(-10)
def adjust_hue(percent)
percent /= 100.0
percent += 1.0
percent = [ percent, 2.0 ].min
percent = [ 0.0, percent ].max

hsl = to_hsl
hsl.h *= percent
hsl.to_rgb
end

# Returns the red component of the colour in the normal 0 .. 255 range.
def red
@r * 255.0
end
# Returns the red component of the colour as a percentage.
def red_p
@r * 100.0
end
# Returns the red component of the colour as a fraction in the range 0.0
# .. 1.0.
def r
@r
end
# Sets the red component of the colour in the normal 0 .. 255 range.
def red=(rr)
@r = Color.normalize(rr / 255.0)
end
# Sets the red component of the colour as a percentage.
def red_p=(rr)
@r = Color.normalize(rr / 100.0)
end
# Sets the red component of the colour as a fraction in the range 0.0 ..
# 1.0.
def r=(rr)
@r = Color.normalize(rr)
end

# Returns the green component of the colour in the normal 0 .. 255 range.
def green
@g * 255.0
end
# Returns the green component of the colour as a percentage.
def green_p
@g * 100.0
end
# Returns the green component of the colour as a fraction in the range 0.0
# .. 1.0.
def g
@g
end
# Sets the green component of the colour in the normal 0 .. 255 range.
def green=(gg)
@g = Color.normalize(gg / 255.0)
end
# Sets the green component of the colour as a percentage.
def green_p=(gg)
@g = Color.normalize(gg / 100.0)
end
# Sets the green component of the colour as a fraction in the range 0.0 ..
# 1.0.
def g=(gg)
@g = Color.normalize(gg)
end

# Returns the blue component of the colour in the normal 0 .. 255 range.
def blue
@b * 255.0
end
# Returns the blue component of the colour as a percentage.
def blue_p
@b * 100.0
end
# Returns the blue component of the colour as a fraction in the range 0.0
# .. 1.0.
def b
@b
end
# Sets the blue component of the colour in the normal 0 .. 255 range.
def blue=(bb)
@b = Color.normalize(bb / 255.0)
end
# Sets the blue component of the colour as a percentage.
def blue_p=(bb)
@b = Color.normalize(bb / 100.0)
end
# Sets the blue component of the colour as a fraction in the range 0.0 ..
# 1.0.
def b=(bb)
@b = Color.normalize(bb)
end

# Adds another colour to the current colour. The other colour will be
# converted to RGB before addition. This conversion depends upon a #to_rgb
# method on the other colour.
#
# The addition is done using the RGB Accessor methods to ensure a valid
# colour in the result.
def +(other)
other = other.to_rgb
rgb = self.dup

rgb.r += other.r
rgb.g += other.g
rgb.b += other.b

rgb
end

# Subtracts another colour to the current colour. The other colour will be
# converted to RGB before subtraction. This conversion depends upon a
# #to_rgb method on the other colour.
#
# The subtraction is done using the RGB Accessor methods to ensure a valid
# colour in the result.
def -(other)
other = other.to_rgb
rgb = self.dup

rgb.r -= other.r
rgb.g -= other.g
rgb.b -= other.b

rgb
end

# Retrieve the maxmum RGB value from the current colour as a GrayScale
# colour
def max_rgb_as_grayscale
Color::GrayScale.from_fraction([@r, @g, @b].max)
end
alias max_rgb_as_greyscale max_rgb_as_grayscale

def inspect
"RGB [#{html}]"
end
end

require 'color/rgb-colors'
```

The error:
```
/home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/parser.rb:50:in `on_error': parse error on value "=" (tEQL) :(file):59 (RuntimeError)
from /usr/lib/ruby/2.0.0/racc/parser.rb:258:in `_racc_do_parse_c'
from /usr/lib/ruby/2.0.0/racc/parser.rb:258:in `do_parse'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/parser.rb:22:in `parse_to_sexp'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/parser.rb:17:in `parse'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/compiler.rb:67:in `compile'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/compiler.rb:8:in `compile'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/cli.rb:113:in `show_compiled_source'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/lib/opal/cli.rb:29:in `run'
from /home/meh/.gem/ruby/2.0.0/gems/opal-0.6.0/bin/opal:14:in `'
from /home/meh/.gem/ruby/2.0.0/bin/opal:23:in `load'
from /home/meh/.gem/ruby/2.0.0/bin/opal:23:in `

'
```